I'd like to point out that vet 3 Guards will beat vet 5 Falls most of the time even without DP-28 upgrade.
Still I don't think that provided "proof" is not enough evidence to call for Guards nerf as I think it is not valid to compare Guards to Falls in terms of direct combat efficency.
If ullumulu kept making his tests, we'd see that commandos losing to LMG grens all the time, because he always uses that no micro, no cover, no ability method which does not give an accurate representation of squads performance.
Falls and guards have completely different roles.
Guards are meant to fight directly as a frontline infantry.
Falls are not, obviously falls will be losing to everything that isn't a perfect situation for them-they have all the tools to create these perfect situations for them and are supposed to do it. Its infiltration infantry that picks their engagements, there is no logical reason why they would ever be fighting other squad out of cover and outside of optimal distance as they are able to close that distance if needed or engage from favorable cover position if wanted. Even capture points will have a cover for them to decide if they want to pick a fight and when.
Vet 5 is hardly an argument as well as 2 out of these stars are non combat utilities most of the time, OKW is no longer resource starved faction and they no longer are supposed to roflstomp everything at vet5.